The present invention relates to an improvement of a connector engagement device which is mainly adapted for mutual connection of connection terminal sets each having a large number of connection terminals such as car wire harness, so that mutual connection locking of a pair of female and male connectors is performed under a small insertion removal force by leverage of an operation cam lever.
As a general connector engagement device for performing connection under a small insertion removal force by using such an operation cam lever, for example, there is such a configuration as disclosed in Japanese Utility Model Unexamined Publication No. Hei. 4-29179. Hereupon, the outline of the conventional configuration and the state of the engaging operation are shown in FIGS. 9 through 12 successively.
In the configuration shown in each of FIGS. 9 through 12, the conventional connector engagement device for performing connection under a small insertion removal force comprises a pair of female and male connectors 81 and 91, and an operation cam lever 101. The female connector 81 has a housing portion 82 in which a set of connection terminals (not shown) are received so as to face the connection opening end portion side of the housing portion 82 and has a pair of fulcrum axis pins 83 each formed so as to project on a connectionwise center line Sb corresponding to the nearly middle portion of effective overall width w1 on a connection end portion side of each of the opposite sides (only one side is illustrated in the drawings) of the housing portion 82. Similarly to the female connector 81, the male connector 91 has a housing portion 92 in which a set of connection terminals (not shown also in this case) to be connected to the set of connection terminals of the female connector 81 are received so as to face the connection opening end portion side of the housing portion 92 and has a pair of engagement pins 93 each formed so as to project on a connectionwise center line Sb corresponding to the nearly middle portion of effective overall width w2 on a connection end portion side of each of the opposite sides (only one side is illustrated in the drawings also in this case) of the housing portion 92. The operation cam lever 101 is designed so as to be mounted to cover the opposite sides of the female connector 81 and rotatably pivotally supported on the fulcrum axis pins 83, and is provided with a pair of cam grooves 102 formed in its opposite sides so that the male connector 91 can be pulled toward the female connector 81 side under the condition that the two engagement pins 93 of the male connector 91 on its opposite sides are engaged with the two cam grooves 102 of the operation cam lever 101 in its opposite sides, respectively.
Thus, as the operation cam lever 101 is operated to rotate, the connection opening end portion of the male connector 91 is fittingly received or inserted into the connection opening end portion of the female connector 81 so that the sets of connection terminals of the male and female connectors can be mutually connected to each other.
Each of the cam grooves 102 of the operation cam lever 101 is composed of: a lead-in opening portion 102a which can receive, without any stress, a corresponding one of the engagement pins 93 of the male connector 91 in the condition that fulcrum axis pins 83 of the female connector 81 are set to be pivotal points of the operation cam lever 101 and the operation cam lever 101 is held in its open position; a guide cam groove portion 102b connected to the lead-in opening portion 102a and extended so as to gradually approach the pivotal points; and a locking groove portion 102c located at a terminal connected to the guide cam groove portion 102b for holding the engagement pin 93 of the male connector 91 at a locking position of the operation cam lever 101 in the state that the operation cam lever 101 has been rotated into the locking position.
Accordingly, in the case of the aforementioned conventional connector engagement device, when the set of connection terminals of the male connector 91 are first temporarily connected to the set of connection terminals of the female connector 81 by shallow insertion of the male connector 91 into the female connector 81 in a state (FIG. 9) in which the connection opening end portion of the male connector 91 is put so as to face the connection opening end portion of the female connector 81, the engagement pins 93 of the male connector 91 are led into the lead-in opening portions 102a of the operation cam lever 101 which are held in the open position in the state that the cam lever 101 is pivotally supported on the female connector 81 (FIG. 10).
When the operation cam lever 101 on the female connector 81 is then rotated in the engagement direction shown by arrow around the pivot point of the fulcrum axis pins 83 in the aforementioned condition, the engagement pins 93 of the male connector 91 led in the lead-in opening portions 102a of the operation cam lever 101 are guided by the guide cam grooves 102b which are formed so as to be made closer to the pivot point gradually to the fulcrum axis pins 83. As a result, the engagement pins 93 are pulled to the engagement position gradually by a relatively small rotational-direction operating force because of the leverage around the pivot point of the guide cam groove portions 102b, so that the set of connection terminals of the male connector 91 are connected gradually deeply to the set of connection terminals of the female connector 81. When the engagement pins 93 reach the respective terminals of the guide cam groove portions 102b, the two sets of connection terminals are connected to each other (FIG. 11).
When the rotating operation of the operation cam lever 101 is further continued, the engagement pins 93 are received respectively in the locking groove portions 102c to thereby lock the state of connection of the set of connection terminals of the male connector 91 in the set of connection terminals of the female connector 81. Thus, the complete connection is finished (FIG. 12). In this connection completion state, the engagement pins 93 of the male connector 91 are moved toward the female connector 91 side to a predetermined distance on the connectionwise center line Sb in the direction of connection which passes through the pivot point of the female connector 81 and held there.
Incidentally, the locked connection state can be unlocked easily by an operation reverse to the aforementioned operation.
In the aforementioned conventional connector engagement device, however, the pair of engagement pins 93 projected on the male connector 91 are pulled toward the female connector 81 side by the pair of guide cam groove portions 102b formed in the operation cam lever 101 which is mounted on the female connector 81 so as to be pivotally supported so that the overall mutual connection of the set of connection terminals of the male connector 91 to the set of connection terminals of the female connector 81 is performed by a small insertion removal force effected by the leverage. Accordingly, particularly because of the operating force applied in the later stage of the connecting operation, when the state of connection of the set of connection terminals of the male connector 91 into the set of connection terminals of the female connector 81 is seen on the whole, the operation cam lever 101 becomes such that, upon completion of the connecting operation, the connection operating force B of the operation cam lever 101 on the connecting operation terminating end b side is inevitably stronger than the connection operating force A on the connecting operation initiating end a side. As a result, these connection operating forces have the relation A&lt;B.
Accordingly, if the connection operating forces applied at the time of the mutual connection of the two sets of connection terminals of the female and male connectors 81 and 91 are unbalanced between the connecting operation initiating end a side and the connecting operation terminating end b side with respect to the operation cam lever 101, the direction of fittingly connection of the male connector 91 into the female connector 81 is apt to be disposed toward the connecting operation terminating end b side on the predetermined connectionwise center line Sb. Accordingly, there arises a disadvantage in that the smoothness of the connecting operation is impeded. On the other hand, the connecting operation initiating end a side subjected to the connection operating force A weaker than the connection operating force B is apt to be floated up in the direction of non-connection because of the stronger connection operating force B given to the connection terminating end b side. Accordingly, the connecting operation initiating end b side is apt to become unstable, so that it becomes impossible to give required uniform contact pressure between all the connection terminals. Consequently, there arises a problem that lowering of reliability on the mutual connection is brought about.